The specification relates to Scanning Near Field Optical Microscopy (SNOM) and in particular to Infrared (IR) SNOM for acquiring information indicative of the optical properties and/or material composition of a surface that directly correlates to infrared absorption spectrum.
s-SNOM and in particular s-SNOM performed in the IR may be a useful technique for measuring and mapping optical properties/material composition of some surfaces with resolution approaching nanometer scale. Various aspects of the technique are described in U.S. applications Ser. Nos. 13/835,312, 14/322,768, 14/634,859, 14/957,480, and 15/249,433 by common inventors and commonly owned with this application. These applications are incorporated by reference in their entirety. AFM-IR may be a useful technique for measuring and mapping optical properties/material composition of some surfaces with resolution approaching nanometer scale. Various aspects of the technique are described in U.S. Pat. Nos. 8,869,602, 8,680,457, 8,402,819, 8,001,830, 9,134,341, 8,646,319, 8,242,448, and U.S. patent application Ser. Nos. 13/135,956 and 15/348,848 by common inventors and commonly owned with this application. These applications are incorporated by reference in their entirety.